A valentine greeting card from the 1920s on display at the History Museum at the Castle in Appleton, Wis., Feb. 11, 2014. (WLUK/Pauleen Le)

Photos: The evolution of valentines

A display at the History Museum at the Castle in Appleton, Wis., showcases elaborate paper lace valentines and 1910 postcards.

Damage at Ramblewood Apartments in Wyoming caused by a roof leak due to ice dams. (Feb. 11, 2014)

Ice dams lead to leaky roofs

The problem happens when ice builds up on roofs, becoming thicker with every thaw and freeze cycle.